New rules curbing credit card company shenanigans took effect Sunday, as restrictions on “unreasonable late payment and other penalty fees” will now block the companies from charging excessive levies if users, to cite just one choice example, do not use their cards.

Those credit card holders who pride themselves on paying their bills on time, and who have enjoyed rewards in the past for so doing, are in for an unpleasant surprise: They may soon be targeted by the very companies that used to ply them with perks.